Reduce dblock-size possible?

I tested the COMPACT process on a copy of a job and it seems to have done the trick - eventually. Feel free to test yourself, or assume my results are valid and apply to your live backup (YMMV).


My test process…

I made a copy of an existing job by:

  • copy backend files to new folder
  • export job as file
  • import job from file
  • edit name so unique
  • edit dest. to point to copy
  • disable schedule

I then ran the following against it by:

  • Go to job menu -> Commandline
  • select “Command” Compact
  • leave “Target URL >” alone
  • Remove all Commandline arguments
  • Use “Edit as text” for “Advanced options” and replace EVERYTHING with this:
--small-file-max-count=0
--small-file-size=0b
--threshold=0
--compression-module=zip
--send-mail-any-operation=false
--dbpath=/data/Duplicati/CTRKXBLMSD-TEST.sqlite
--encryption-module=aes
--dblock-size=40MB
--retention-policy=7D:U,1M:1D,1Y:1W,U:1M
--passphrase=xxxxx

It seems to have happily re-compressed 30% of the files from the default 50MB dblock size to the reqiested 40MB on the first run then stopped w/out error. I ran the process again, and it processed the rest of the files to the new 40MB dblock size.

Why it took two runs I don’t know.

I have a full-verification test running now just to make sure everything is good as this also seems to have converted my very old .7z dblock files to .zip (yay!).

Note that the progress bar just said “Running task: Starting backup …” the whole time, so estimating how long it will take is tricky. :slight_smile:

For those that care, here are the first & last few lines of the PROFILING console log:

The operation Compact has started
Starting - Running Compact
Found 0 fully deletable volume(s)
Found 0 small volumes(s) with a total size of 0 bytes
Found 93 volume(s) with a total of 0.00% wasted space (0 bytes of 4.08 GB)
Compacting because there is 0.00% wasted space and the limit is 0%
Starting - RemoteOperationList
Backend event: List - Started:  ()
  Listing remote folder ...
Backend event: List - Completed:  (276 bytes)
RemoteOperationList took 0:00:00:00.035
...
Starting - CommitCompact
CommitCompact took 0:00:00:00.262
Running Compact took 0:00:28:07.987
Return code: 0
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